#weekendusers How did humans live 5000 years ago?

Researchers from the Cyprus Institute, in collaboration with the Iranian Center of Archaeological Research, have worked around the clock for a week on ID16A to discover more about the lifestyle of our ancestors.

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How did people live 5000 years ago? What did they eat? What can we learn of their health? Were they exposed to contaminants? To answer these questions with various techniques researchers first need to understand more about the preservation state of ancient human hair. In order to do this, a team from Cyprus Institute is scanning hair remains found within burials at the ancient site of Shahr-I-Sokhta, in Iran. In this urban settlement, at a crossroads of important ancient trade routes that later became part of the Silk Road, there was busy commercial and manufacturing activity around metal and precious materials as evidenced by the artifacts found onsite during archaeological excavations. Archaeologists have also found remains of the inhabitants of the city dating to the 3rd millennium BC, and their state of preservation is remarkable. “The climate in this area is very arid and hot, and this has led to preservation of body tissues not often found with human skeletons, including hair”, explains Kirsi Lorentz, assistant professor at the Cyprus Institute.

Lorentz, together with two team members, Simone Lemmers and Yuko Miyauchi, and in collaboration with Professor Mansur Sajjadi from the Iranian Center of Archaeological Research, and Charalambos Chrysostomou, an imaging expert at the Cyprus Institute, has come to the ESRF’s ID16A to work with Julio da Silva with ancient hair samples to explore the preservation status and changes to the internal structure of the hair strands, in order to use this as a basis to study more about the lifestyle of our ancestors. “Human scalp hair, when sufficiently preserved, can provide crucial information about past human activities, health, disease, environmental exposure, or even hair colour, and within this context, it is even more important to be able to characterise the preservation status of these ancient hair samples”, explains Lorentz.

The team has used the holographic-tomography technique on beamline ID16A. Because hair absorbs X-rays only weakly, the team needed phase-contrast imaging to be able to explore its nanostructure, specifically holographic-tomography, to be able to probe the hair at the nanoscale. The technique allows the researchers to explore any differences between the different individuals sampled, focusing on the melanin granules in the cortex, and the amount of fungi and other deterioration processes affecting the hair.

Modern hair samples will also go through the X-rays as control samples. “We are taking samples from people with different hair colours, hair thickness, and type, so that we can compare them”, explains Simone Lemmers, a post-doctoral researcher at the Cyprus Institute.

This is the first time that such a study is done with synchrotron radiation at the nanometre scale. If successful, Lorentz says that “this type of data will potentially revolutionise the level of detail we are able to extract as to individual life histories in the past”. “Such close-up encounters with real individuals from the past will contribute towards convincing humanity to preserve its common cultural heritage for the generations to come”, she concludes.

Text and video by Montserrat Capellas Espuny

Top image: Aerial view of the Shahr-I-Sokhta site, in Iran. Credits: Media Rahmani